Way back at the start of the season, amid all the whistles and fouls, the defensive-minded teams appeared to be in trouble, a seemingly dying breed hamstrung by the NCAA's new hands-free rules.

As the season progressed, the top coaches and teams adjusted to the changes and found ways around the impediments.

Now, after the all increases in scoring and shooting percentages and offensive flow, the season has come down to a Final Four of teams held together by one common thread: shutdown defenses.

"In general, it's like most sports: Defense wins championships," said Bill Frieder, a longtime coach and TV/radio analyst. "You still need to score, but basically when it gets right down to it, you have to make stops. The teams that can make a stop or two back to back are the teams that advance."

The Final Four teams in this wild ride of an NCAA tournament earned a trip to North Texas this weekend because they can do just that.

Florida is the best defensive team in the country, allowing just 88.5 points per 100 possessions, according to the analytics of KenPom.com. The Gators can be downright dominating on the defensive end, swarming ballhandlers and luring shooters into a fall sense of security before rising up to swat shots back in their faces.

Defense has been a cornerstone for Bo Ryan since he won four national championships at Division III Wisconsin-Platteville and it's been the calling card -- along with that ultra-patient offense -- since he arrived at Wisconsin. The Badgers are fundamental and fierce, allowing about 56 points a game to NCAA opponents -- nearly eight less than before the tournament.

For all the flash of Kentucky's fabulous freshmen, these young Cats can get after you on D. Kentucky's latest one-and-done lineup is filled with long, athletic players who can harass on the perimeter and guard the rim -- 10th nationally with 6.1 blocked shots per game -- like few teams in college basketball.

And for all the hype heaped on Connecticut's Shabazz Napier, the Huskies are pretty husky when it comes to defense. Ryan Boatright has become a point-guard stopper -- he had four steals and helped limit Michigan State's Keith Appling to two points in the East Regional final -- and UConn seems to have an entire roster of rim protectors, ranking 16th nationally with 5.8 blocked shots per game.

"We are predators out there," UConn coach Kevin Ollie said.

In most years, the high-scoring teams often get the attention, whether it was Florida Gulf Coast's Dunk City a year ago or back to Houston's Phi Slamma Jamma of the early 1980s. What usually happens at the finish? The best defensive teams end up with the hardware.

Louisville rode its swarming, chaos-inducing defense to a title last season.

The year before that, Anthony Davis and Kentucky's shot-swatting young Cats set an NCAA record with 335 blocked shots on their way to the national championship.

In 2011: Connecticut 53, Butler 41.

Great defensive teams litter the list of national champions throughout history, too.

UNLV ran its wrecking crew through the bracket in 1990. North Carolina State and Georgetown let the air out of Phi Slamma Jamma in consecutive title games. Indiana played superb team defense during the last perfect season in 1976. Lew Alcindor and Bill Walton anchored the UCLA teams that ran off 10 titles in 12 years.

Go all the way back to the 1950s and the San Francisco teams that won consecutive championships had a young Bill Russell dominating the middle before he went on to do the same thing for the Boston Celtics.

"In the NBA, it's always seems to come down to the teams that play the best defense and it's no different in college basketball," Arizona State associate head coach Eric Musselman said. "At the end of the day, no matter how well you score, you've got to be able stop people."

The Final Four teams have proven they can do it so far in the tournament.

Wisconsin opened the NCAA tournament by holding American to 35 points and reached the Final Four by preventing Arizona from getting off a potential game-winning shot before the buzzer sounded in overtime.

Kentucky held Kansas State to 49 points in its NCAA opener and held Michigan scoreless for nearly 4 1/2 minutes of a three-point Midwest Regional final win that sent the Wildcats to the Final Four for the third time in four seasons.

UConn went toe-to-toe with one of the nation's best defensive teams in the East Regional final, holding Michigan State to 39 percent shooting and two field goals -- one at the buzzer after the game was decided -- over the final 5 minutes.

Florida is the third team in NCAA tournament history to win four games by double digits and hold opponents under 70 points per game en route to the Final Four, limiting teams to an average of 55 points per game.

"We just take so much pride into being able to disrupt the team and being able to lock down guys," Florida forward Patric Young said.

So do the other three teams, a big reason why they're all together in North Texas.